This invention relates to portable ramps and more particularly, portable ramps that allow high centering wheeled lawn equipment, such as commercial walk-behind lawnmowers, to safely and easily traverse over curbs.
Wheeled lawn care equipment, such as commercial walk-behind mowers (“walk-behinds”), zero-turning radius riding mowers and tractors, must sometimes traverse over curbs and other obstructions in order to get to grass cutting and work areas. Traversing curves causes added wear and tear on the equipment and, in many cases, results in damage to the equipment. Traversing curves also places the user at risk of serious injury. Damage and injury are particularly problematic with commercial or large walk-behinds, that is, mowers having mower decks of 30 inches or more. These mowers tend to be “high centering” because the lighter mower deck sits forward of the engine that propels the mower forward and drives the cutting blades. Other types of wheeled lawn equipment, such as riding mowers and tractors, also have this high centering characteristic.
Traversing a curb with a large walk-behind requires that the user “pop-a-wheelie” with the mower, exerting downward force on the handles to lift the front wheels a sufficient height off the ground to clear the curb. Because large walk-behinds are high centering as well as heavy, they are difficult to control, especially as the power-driven rear wheels contact the face of the curb and traverse the curb. Once over the curb, the walk-behind often weaves sand bounces as the front swivel wheels lower and contact (or slam into) the ground.
Newer designs of walk-behind mowers, called “standups” or “right standups,” have a deck similar to that of traditional walk-behind mowers but are heavier, with the motor and transmission in a different location. Furthermore, because the user stands on a platform when using the mower, the mower handles are located higher up than those of a traditional walk-behind. The additional weight of the mower combined with the higher handle location makes a standup mower nearly impossible to pop up over a curb.
To solve these problems, some users rely on boards or other ramp-like devices in an attempt to eliminate these problems but boards and similar devices often break slip or slide off of the curb during use, are cumbersome to use, may be set non-parallel to one another or at an improper distance, and are usually not readily accessible when needed because they cannot be stowed on the equipment. More importantly, none of these devices account for the high centering characteristic of the larger walk-behind mowers. Again, the user must often pop-a-wheelie in order to place the front swivel wheels onto the board
Several portable ramps have been designed to help wheeled lawn equipment traverse a curb. For example, U.S. Pat. No. 6,044,511, issued to Frost et al. on Apr. 4, 2000, discloses a portable ramp that has a curved bottom designed to allow it to hug the shape of a curve. Troughs on the top surface provide traction and magnets may be attached to or embedded in the bottom surface so the ramp can be removably secured to metal on the top of wheeled vehicles and equipment. Because the ramp is designed to go over the top of the curb, the ramp does not account for the high centering characteristic of large walk-behinds. The front swivel wheels of a large walk-behind remain airborne as the front wheels leave the ramp and the rear wheels continue to traverse the ramp. The ramp also does not allow a user to establish a pre-set distance between the ramps. Users, particularly those in the landscaping and lawn service business, tend to not use ramps if the ramps must be spaced apart and adjusted each time a curb or other obstruction is to be traversed. The lawn care business is a very competitive, cost-conscious, time-sensitive, and transient business. Any task that requires additional cost or time at the job site is simply not done. Additionally, because the ramp requires ridges to provide the necessary traction, the top surface of the ramp traps dirt, oil and debris that lessen the effectiveness of the ridges over time.
The CURB JUMPER™ Ramp (Walker Manufacturing Company, Fort Collins, Colo.), avoids the adjustability problem by providing a single, 40-inch wide ramp that spans the distance between wheels on a 42- and 48-inch riding mower. Although this ramp does not extend over the top of the curb, it includes ridges that collect dirt and debris and is designed to be backed over, making it unsafe for use with a walk-behind. Even if not backed-over, the ramp is not convenient for use with walk-behinds because there is no place on the mower deck to stow such a large ramp. Users in landscaping and lawn service tend to not use a ramp if it cannot be stowed on the equipment and readily accessible for use. The ramp is expensive, making it economically unattractive to landscapers and lawn services that own multiple walk-behind mowers.
The CURB-UP™ Ramp (Discount Ramps.Com, LLC, West Bend, Wis.), is an adjustable lawn tractor metal curb ramp that has a threaded adjustable connecting rod located between the ramps. Although this ramp does not extend over the top of the curb, it can only be stowed on the user's lap while the lawn tractor is in use. The metal edges of the ramp present an additional safety hazard to users. The threaded rod makes the ramp inconvenient for use with walk-behind mowers (there is no “lap” to store it on”) and precludes quick changeover to a different between-ramp distance.
Last, some manufacturers are trying to avoid the need for curb ramps altogether by redesigning their walk-behind mowers to provide features that make it easier to “hop” a curb. The Toro Company, for example, advertises a “T-Bar Curb Hopper Design” on its mid-size walk-behind mowers.